Which of the following is NOT a reason older adults are at higher risk for vitamin D deficiency?

• A. More likely to stay indoors
• B. Reduced ability to synthesize vitamin D in the skin when exposed to sunlight
• C. Regular outdoor sun exposure
• D. Use of sunscreens

Answer: (C)

Regular outdoor sun exposure helps prevent vitamin D deficiency because UVB exposure stimulates the skin to make vitamin D, boosting overall stores. In older adults, however, several factors raise the risk: aging reduces the skin’s ability to synthesize vitamin D with sunlight, many spend more time indoors, and sunscreen use blocks UVB from reaching the skin. These limitations lower vitamin D production, increasing deficiency risk. Therefore, regular outdoor sun exposure is not a risk factor; it actually reduces the risk. If sun exposure is limited, relying on dietary sources or supplementation becomes important to maintain adequate vitamin D status.